The concept of Sustainable Urban Drainage Systems (SUDS) Quantity, Quality, Amenity Managing Stormwater in the City of the Future H. Sieker Ingenieurgesellschaft Prof. Sieker (IPS), Berlin, Germany
Curriculum Vitae Heiko Sieker 1986-1991: Civil Engineering (University Hanover) 1991: Master degree in water resources with specialization in a) Water resources management b) Urban drainage and waste water treatment c) Fluid dynamics 1992-1997: Consultant in Hamburg & Berlin Since 1998: Manager of IPS 2000: PhD-Thesis (University of Darmstadt): Urban drainage master planning Since 2006: Lectureship at the Technical University of Berlin Managing Stormwater in the City of the Future Page 2
Owner/Manager: Consulting company IPS a) Prof. Dr. Friedhelm Sieker, Hanover b) Dr. Heiko Sieker, Berlin Staff (17): Civil & Environmental engineers, Geographers Specialized on Urban Water Management a) Engineering Design & Master planning b) Software development c) Applied research d) Invention (Patents) e) Education (Seminars, Books) More information www.sieker.de THE STORMWATER EXPERTS INGENIEURGESELLSCHAFT PROF. DR. SIEKER MBH Managing Stormwater in the City of the Future Page 3
Sustainable Urban Drainage Managing Stormwater in the City of the Future Page 4
Conventional Drainage Paradigm Shift a) Separate or combined systems b) Terms: Drainage, Disposal c) Getting rid of stormwater as quick as possible Modern approach a) Infiltration, Green roofs, Rainwater harvesting, Constructed wetlands, Throttled discharge b) Terms: BMPs, SUDS, WSUD, LID c) Maintain natural water balance Managing Stormwater in the City of the Future Page 5
Conventional Drainage Managing Stormwater in the City of the Future Page 6
Modern approach Outlet of 100 hectare commercial development! Managing Stormwater in the City of the Future Page 7
Conventional Drainage Paradigm Shift a) Separate or combined systems b) Terms: Drainage, Disposal c) Getting rid of stormwater as quick as possible Modern approach a) Infiltration, Green roofs, Rainwater harvesting, Constructed wetlands, Throttled discharge b) Terms: BMPs, SUDS, WSUD, LID c) Maintain natural water balance Managing Stormwater in the City of the Future Page 8
Disturbance of Water Cycle Source: US-EPA Managing Stormwater in the City of the Future Page 9 Quelle: US-EPA, 2004 (angepasst)
Increase of runoff Natural water cycle Urban water cycle High Evapo- Transpiration Low Evapo- Transpiration Low Surface runoff High Surface-runoff High Groundwaterrenewal Low Groundwaterrenewal Pictures: Geiger/Dreiseitl Managing Stormwater in the City of the Future Page 10
Urban Flooding Athens, Greece, 2007 Managing Stormwater in the City of the Future Page 11
Impact on water quality Managing Stormwater in the City of the Future Page 12
Pollution from Stormwater Heavy metal emissions in 2000 Target value Groundwater Avulsion Urban areas Atmospheric deposition Industrial discharges Drainage in agriculture Erosion Drift for farming Mining activities Municipal waste water treatment plants Source: Official WFD-Article5-report for Germany Managing Stormwater in the City of the Future Page 13
Impact on River Morphology Pictures: Podraza Managing Stormwater in the City of the Future Page 14
Cost of Stormwater Drainage Germany: most municipalities have a stormwater fee Cost for stormwater drainage is not included in fees for drinking water and waste water Base for stormwater fee: area connected to sewer Typical fee (Berlin): ~2 /m²/year Examples for fees a) Private house (150 m² connected) 300 /year b) Supermarket (10.000 ² connected) 20.000 /year c) Supermarket (disconnected, infiltration) 0 /year Managing Stormwater in the City of the Future Page 15
Paradigm Shift Development of new strategies in last 10-15 years New technical rules New legal regulations : a) Water Framework Directive in Europe b) Regulation for Infiltration in regional water laws c) New stormwater act has been released 2010 New Term: Stormwater Management Managing Stormwater in the City of the Future Page 16
Objectives Quantity Drainage comfort Flood protection Water balance Objectives of stormwater management Sustainability objectives and indicators => Session on Thursday morning Quality Pollution control Hydraulic Stress Socio-Economy Cost effectiveness Flexibility Amenity Managing Stormwater in the City of the Future Page 17
SUDS Lot of different solutions are possible SW Harvesting Infiltration Transpiration Retention Treatment Drainage Managing Stormwater in the City of the Future Page 18
Example: Hoppegarten Managing Stormwater in the City of the Future Page 19
Example: Hoppegarten Hydrological conditions a) Very low hydraulic capacity b) Max. discharge: 40 l/s (for 100 hectare new development!) c) Runoff at heavy rainfall: 10 m³/s d) Extensive retention necessary Geological conditions a) Glacial history b) Loamy soil (Mergel): k f = 10-7 m/s c) high groundwater tables" d) Pure infiltration not possible Managing Stormwater in the City of the Future Page 20
Swale-Trench-System Soil-layer d-30cm Trough Overflow Trough Manhole Overflow trench Trench Drain pipe Throttle Managing Stormwater in the City of the Future Page 21
Example : Hoppegarten 100 Hectares!! Managing Stormwater in the City of the Future Page 22
Economical Aspects Calculation and comparison of costs Central solution (Storm sewer with retention pond) Decentral solution (Trough-trench-system as constructed) Variant central decentral Total cost 19 /m² 17 /m² Public part 16 /m² 5 /m² Private part 3 /m² 12 /m² Economical advantages a) Shift of investment into the future b) Flexibility: Providing retention as really needed c) Positive effect on compensation measures Managing Stormwater in the City of the Future Page 23
Example: INNODRAIN Prinziple: Infiltration + Retention + Retention + Drainage Applicable in soils with low infiltration capacity (k f < 10-6 m/s) Activated soil layer (treatment of road runoff) Area demand: only 4 % of connected sealed surface! Side effect: slow down traffic More information: www.mallnet.info Managing Stormwater in the City of the Future Page 24
Example : INNODRAIN Managing Stormwater in the City of the Future Page 25
Example : Plötzin Managing Stormwater in the City of the Future Page 26
Stormwater Management New developments a) Many good examples private and public b) Obligatory in Germany c) Decentralized SWM is Best Available Technology (BAT) In existing urban area (retrofitting) a) No obligations b) More difficult compared to new developments c) But: often very beneficiary d) Front runner: Emschergenossenschaft (water board) Managing Stormwater in the City of the Future Page 27
Examples for disconnection Managing Stormwater in the City of the Future Page 28
Examples for disconnection Managing Stormwater in the City of the Future Page 29
Thank you for your attention! Managing Stormwater in the City of the Future